Soviet T-72 Main Battle Tank, Part 1, Revised February 17, 2003

Picture 1:
The Soviet T-72 tank was originally designed as a less expensive version of the Soviet 'state of the art', Kharkov-designed, T-64 main battle tank. From the beginning of the T-64 program there had been jealousy from other tank designers/manufacturers over the decision to build the Kharkov tank, and the complicated T-64 tank had not been well received by everyone in the Soviet military. The T-64 was designed with an automatic loading system for the main gun, and when the announcement was made in 1964 to adopt the T-64 for production, the competing Vagonka design bureau in Nizhni Tagil began experiments to produce an automatic loader for their own T-62 design. Gradually, push came to shove, and the altered T-62 design with autoloader was accepted for production in 1967 as the T-72. The new design was accepted for full-scale production in 1971 after prototypes were built and tested, and the T-72 tank was born.

The Soviet's decision to simultaneously build both the T-64 and T-72 tanks was a compromise decision between those in the military demanding the most sophisticated tank possible to compete with NATO's best (the T-64 was complicated and expensive), and the Ground Forces who desired the greatest number of tanks (The T-72 was simpler and less expensive). The decision to build both vehicles produced a difficult situation for the Soviet Army because most of the two vehicle's parts were different, the primary common component being the ammunition for the 125mm gun. Production of the new T-72 tanks was first undertaken by the Ural Railcar Plant in Nizhni Tagil. Manufacturing was later extended to the Chelyabinsk Machinery Plant when it ceased production of the T-55 and T-62 tanks for export. The plants at Omsk and Kharkov were then used to produce the higher cost T-64 tank, and later the expensive T-80. The T-72 in this photo is a Finnish Army T-72M1, an export T-72 built by Poland under license. You can see Finland's identifying blue and white national roundel behind the turret smoke dischargers.

We are lucky to be able to explore the interior of three different T-72 tanks through color photographs taken by Mr. David S. Speaks and Mr. Deon de Lange. The first vehicle is a T-72 in the collection of the Threat Training Facility (TTF), which is maintained by the 547th Intelligence Squadron of the United States Air Force, located at Nellis Air Force Base, Nevada. As we have mentioned elsewhere in AFV INTERIORS (ZSU-23-4), the TTF encourages military study of their collection, allowing visitors access to the interiors of their collection vehicles for examination. The second tank is a T-72M1 and part of the vehicle collection at Fort Stewart Museum in Georgia. The third vehicle is another T-72M1, this one located in the South African Defense Forces (SADF) Museum of Armour. Because of the excellent quality of both Mr. Speaks' and Mr. de Lange's digital images, we have produced the pictures in large format and extended the T-72 series out to a number of web pages. This first page will introduce you to the developmental history and general layout of the vehicle, using currently available diagrams and illustrations. The other six parts of this series will then allow you to explore the interior of the TTF Nellis T-72, Ft. Stewart T-72M1, and SADF Museum of Armour T-72M1.

Picture 2:
We will begin our basic familiarization of the T-72 with some drawings and cross-sections. These drawings of their first production T-72 were produced by the Soviets in the early 70's, and originally included Russian captions and labels. But the drawings have been reproduced many times with the identification tags translated into other languages, and in our case we have the US Army recognition version of the sketches, with the labels written in English. Unfortunately, the labels are not all correct.

Overall, the general layout is very similar to the T-62 from which the design originated, but with some later T-64 influences. Like the T-64, the crew is composed of only three men due to the use of an autoloader. The driver's seat (20) is centrally located in the bow and the commander and gunner are placed in the turret, with the gunner (18) on the left side of the big gun. The T-72 design is low and wide, with the inherent positive and negative results of such a design, which we will examine in these pages. The main gun is a huge 125mm smooth bore weapon, utilizing separate charge and projectile ammunition. Roughly half of the ammo is stored in a revolving cassette magazine (16) under the turret, and the remainder is stored in racks in the turret and hull. The engine (13) is transversely mounted in the rear of the hull behind a firewall, and the transmission (14) is located directly behind the engine at the rear of the tank. Suspension is via torsion bars that cross the hull floor, and includes six road wheels and rear drive sprockets.

Picture 3:
A second interior drawing of the Soviet T-72 tank shows the layout inside the hull and turret looking forward. Again, notice how wide and short the overall design is. With the ammo carrousel taking up space under the turret, it does not leave much room for the commander and gunner above. The large breech of the 125mm weapon (25) dominates the center of the drawing, and the commander's vision instruments (27), storage for coax MB ammo (29) and radio (30) are identified. The PKT coaxial MG (26) is also on the commander's side of the big gun.

On the opposite side of the turret are the gunner's controls and components. These include his TPN night sight (7) mounted next to his TPD range finder sight (6), with the gun's elevation handwheel (5) mounted below. Off to the left of the handwheel is the traverse indicator, or azimuth dial (24), although it is not drawn particularly well here. The turret hand traverse wheel (23) is identified, as well as the location of the gunner's primary hydraulic/electrical power traverse/elevation controls (31). Let's take a closer look now at enlargements of these drawings for a better feel for each tanker's assignment.

Picture 4:
This enlargement of the driver's area from the earlier drawing is a bit fuzzy, but it does provide us with basic information about his position. The seat is well padded and comfortable in the Soviet tradition, and secured to supports bolted directly to the hull floor below. To either side of the driver's feet are the steering handles (2); the use of steering tillers is one of the more antiquated components of an otherwise fairly modern machine. To the driver's right is his gearshift (4), and components of the NBC protection system (3 and 19). The pedals in front of his seat include the normal clutch, brake, and accelerator, with portions of the braking system being identified here (21).

Although not identified here with a number, you might be able to see that the driver has a single vision periscope mounted forward of his over-head hatch. This is a wide angle TVNE-4E day observation periscope. The hatch is the type that elevates a few inches and then swings to the side, the control for the hatch being the cylindrical object you see attached to the ceiling and hanging down just behind (to the right) of his gearshift. There is so little room between the hatch and the centered gun tube above, that when the turret is centered, the driver can not use his hatch. In that case he is provided with an emergency belly hatch under his seat, the seat bolted directly to the hatch and the hatch opening on hinges. Unfortunately, you can not physically open this hatch while in the driver's forward position because there is so little room (at least I was not able to), so its use in an emergency is questionable. The driver's best chance for an emergency exit is to remove his seat back and squirm back into the turret, exiting then up through one of the turret hatches.

For the driver's hatch to be blocked by the main gun tube when the turret is centered is not unusual for a modern battle tank, especially when you consider the pressure to reduce the overall silhouette, but the inability to open the emergency belly hatch for a quick egress is odd. In most western designed tanks, the hatch does not open upward on hinges like this, but completely drops out, and therefore does not interfere with the exit. The front edge of the ammo carrousel is only a few inches from the back of the driver's seat.

Picture 5:
You would think that with only two crewmen in the turret that there would be some additional room to move around, but just the opposite is true. Each position is surrounded by equipment, and it leads to the feeling that the tank is strapped onto your body, rather than you are sitting in the vehicle. There were three primary types of T-72 produced for Soviet use, the T-72, the T-72A, and the T-72B.

The T-72A was produced from 1979 to 1985 and incorporated a number of improvements over the original design. These improvements included the installation of the TPDK-1 laser ranging sight for the gunner replacing the TPD2-49 coincidence range finder of the T-72, a new TPN3-49 gunner's night sight with the L-4 searchlight in place of his original TPN1-49-23. The T-72A also has continuous side anticumulative screens, a 902B smoke grenade launching system, a 2A46 gun in place of the original 2A26M2, a TVNE-4B driver's night vision device, and a V-46-6 engine. The Warsaw Pact/Export versions of the T-72 include the T-72M, which is the export version of the T-72, and the T-72M1, which is the export version of the Soviet T-72A. Both the T-72M and T-72M1 export versions include additionally strengthened frontal hull and turret armor. Exports of these versions were numerous and included clients of the former Warsaw Pact as well as Algeria, Angola, India, Iran, Iraq, Syria, Algeria, Kuwait, Libya, Finland, and Yugoslavia. My understanding is that there have been manufacturing licenses provided for various T-72 building programs in Croatia, Czechoslovakia, India, Iran, Iraq, Poland, and Yugoslavia.

The T-72B tank has been manufactured since 1985, and the export version is known as the T-72S. The main differences between the T-72A and B tanks consists mainly in the installation of the 2E42-2 stabilizer with electrohydraulic elevating drive and an electromechanical traversing drive instead of the original 2E28M two-plane electrohydraulic stabilizer. There is also an improved guided weapons system, removable container explosive reactive armor, and an improved engine, the V-84, in place of the V-46-6.

Our enlargement shows some of the gunner's equipment in an early T-72. The main armament elevation mechanism (5) is indicated, as well as the early TPD2-49 range finder sight (6) and the TPN1-49-23 IR night sight (7). Most of the rear of the turret space is taken by the autoloader mechanism (10), and what you see here in the drawing includes the hoist, rammer, and ejection port mechanism. The ammo carrousel (16) is under the turret floor and the turret basket (17) is also identified in the image.

Picture 6:
One of the best known properties of the T-72 line is the replacement of the loader in the turret with an autoloader and ammunition carrousel; a drawing of the carrousel is shown here. As I mentioned earlier, the main ammunition reserve consists of 22 projectiles and 22 propellant cases, the projectiles stored on the bottom layer of the carrousel and the Zh-40 cases on top. Each projectile comes packaged in a separate cassette that also contains a semi-combustible case above the projectile. In the T-72A there are twenty-two additional projectiles and cases stored up in the hull and turret. The only ammo stored above the turret lip are five projectiles located near the gunner's and commander's station on later models of the T-72, the rest are in racks down in the hull.

Briefly, once the gunner has selected the desired projectile to load, the carrousel rotates under the turret floor until the projectile type stops under the autoloader hoist at the rear of the turret. The gun is then automatically elevated into the proper loading position and the autoloader hoist brings up the two-piece ammunition cassette from the carrousel. The projectile is first rammed into the breech and then the cassette lowers and the charge is then rammed. The gun then automatically returns to the gunner's previous line of sight as the hoist replaces the empty cassette down in the carrousel. Now, the weapon can then be fired. After firing, the spent stub casing is ejected out the rear of the turret through a small port in the roof while the next cassette is selected in the carrousel and the loading procedure repeated. It takes approximately eight seconds to load a new round and have it ready for firing.

Picture 7:
This is a simple basic schematic of the 2A46M autoloader design. As I mentioned earlier, the ammo carrousel (12) under the turret floor has 22 cassettes located around its perimeter, each with a projectile below and a cartridge case above. The cartridge cases are of the same type, regardless of the projectile type.

Before battle, as the ammunition is being loaded into the carrousel, the gunner records the location of each projectile type in the carrousel. Then, when called to battle and with the gunner indicating on his control panel which projectile the commander has called out, the carrousel automatically rotates until that ammunition type is aligned with the loader hoist. The hoist then lifts the cassette up to the rear of the breech, and when the gun has automatically reached the correct elevation for loading (+3 degrees), the projectile (7) and the case (6) are rammed. Notice that there are two ramming cycles (8 & 9). In the later T-80 autoloader, these operations are combined into one, and the weapon may then be fired more rapidly than the eight rounds per minute of the T-72 autoloader. Firing one round every eight seconds may seem fast to you, but go ahead and count out eight seconds and you will see that it can seem like an eternity if someone is shooting back at you. And don't forget that the gun returns to the position it was last laid. There is always some correction required before it can be fired again, and that takes additional time.

After loading, the gun automatically returns to the prior engagement angle and the gunner may then adjust his aim and fire the weapon. This leads to the interesting gun tube bobbing that is characteristic of a T-72 with autoloader in action. After firing, the base stub from the cartridge case (5) is extracted by the stub case ejector, and after a small hatch has opened in the rear roof, the stub is tossed out the turret. The ejecting of the stub through an open hatch also opens the tank to the possible entrance of NBC exposure, and it has always seemed to me to be a strange design component of these modern Soviet/Russian tanks. The Soviets apparently thought the possible contamination was of less importance than ejecting the smoking stubs out of the vehicle. In this particular drawing, the turret floor (12) and the tank hull bottom plate (11) are both identified.

Picture 8:
This is a more detailed schematic of the 2A46M loader in the T-72, with most of the major components identified, the loader again seen from the right side (the commander's side). The electro-mechanical loader is operated by electric motors and includes the carrousel, cassette hoist, stub-case ejector, rammer, electro-mechanical gun lock (to immobilize the gun while it is being loaded), a memory unit (to return the gun to the gunner's last aiming position), distributor box, control panel, loading platform, and a "rounds left/cassettes empty" indicator.

Storing the ammunition in magazines separated by bulkheads from the tank crew, like found in the M1 Abrams and Leopard 2, has not been common in Soviet tanks. The result is that hits on the T-72 usually produce catastrophic ammunition fires, as evidenced by action in Lebanon in 1982 and the Gulf War. And although most official Soviet/Russian literature suggests that storing the ammo under the turret floor helps reduce the overall height of the vehicle, it is obvious that just the opposite is true. By storing the ammo under the turret floor, the crew headspace is further reduced, cramping their positions even more. Imagine how low the silhouette of this vehicle would be if the ammunition was located in a protected rear turret bustle, as it is in the French Leclerc tank for instance, also equipped with an autoloader.

Picture 9:
Another enlargement of an earlier drawing shows once again the commander's side of the turret. The radio set you see in the center of the image is the R-123M, replaced by the R-173 in the T-72A and later variants. It operates in the FM mode in the range of 30,000 to 76,000 kHz with 10 pre-selected frequencies. And unlike most Western tank radio sets, the R-173M uses a throat mike that is part of the tanker's leather helmet. The same mike system is also utilized with the tank's internal intercom system.

The commander is provided with a rotating cupola into which is mounted his overhead hatch with two rear facing TNPA vision blocks, and three vision devices facing forward (27). While the outer two devices are simple TNP-160 day vision blocks, the central device is the commander's main sight. In most of the T-72 models, this is a target designation sight, the TKN-3. The TKN-3 is a bi-ocular sight that allows the commander to sight a new target by rotating this cupola, and then hand it off to the gunner by pushing a button on the sight handle that traverses the turret to his line of sight. Unlike Western tanks, the commander does not have the same sight picture as his gunner, there is no connection between his sight and the gunner's. But the hunter-killer capability of the TKN-3 system has been a common design of Soviet/Russian tanks for many years, so let's take a closer look at the TKN-3.

Picture 10:
This is a drawing of the commander's TKN-3; we will see examples of the actual unit later in our two tanks. The periscope sight head with the main mirror (4) fits up into and opening in the cupola in front of his hatch, with the remainder of the sight hanging down into the cupola. The securing screw (5) holds the unit together and the shade lever (6) provides control to close or open the protective cover inside the head. The oculars (8) have soft rubber eye cups surrounding them for some eye protection, and a forehead pad (3) is also provided to brace your head while using the sight. During operation, the commander holds the handles (1 & 11) with both hands, and rotates his cupola manually by using these handles.

If the commander spots a target in his sight, he can bring the main gun directly onto his line of sight in azimuth by pressing the button (2) on the left control handle. He can then hand off the target to the gunner after the turret rotates to his view. But if the commander depresses the button (10) on the right control handle, he can override the gunner's traverse and rotate the turret anywhere he pleases by himself. Unlike most Western tank designs, the commander can not fine lay the gun, nor can he fire it. The crew is depends on the gunner for firing the main weapon, and if there is a problem with him, that's the end of the game. The TKN-3 has a built-in infrared night viewing channel, and the magnification for this is 4.2x while the day daylight channel is 5x. The TKN-3 also has an angular field of view of around 10 degrees in day mode, and 8 degrees in night. At night, the commander can also use the cupola mounted OU-3GK infrared searchlight to improve his view, but it has an effective range of only about 400m.

Picture 11:
The 2A46 125mm gun was designed by the famous Petrov design bureau in Perm, and it is a very powerful and accurate weapon. As a smooth bore gun, it can fire a number of different projectiles, including a guided missile in the most recent versions of the weapon. The designation 2A46 is the industrial designation for the weapon, but it is also known as the D-81TM, and has been named the Rapira 3 by the Russians. Typical rounds fired from the weapon include the 3WBK10 or 3WBK7 high explosive anti-tank (HEAT) round, a 3WOF22 high explosive fragmentation (HE-FRAG), or a 3WBM3 (or 3WBM6/7/8) armor-piercing, fin-stabilized, discarding sabot (APFSDS). These ammunition types are said to be also common to the T-64, T-80, T-80 Ukraine, and T-90 since they use the same weapon.

Maximum gun depression is only -5 degrees due to the lack of headroom inside the short turret, and the maximum elevation is +15 degrees. The weapon has a sliding wedge breech block that opens to the left, and the ammunition is fired electrically. If the electric autoloader malfunctions, there are hand cranks to manually load the weapon, but the frequency of firing then drops to two or fewer rounds per minute. Once the carrousel rounds are used up, the crew must laboriously reload it with the other projectiles and cases that have been stored in racks in the turret and hull. This Sovphoto image shows tankers carefully loading the early fragile Zh40 self-consuming propellant cases.

Picture 12:
Except for the ammo in the carrousel under the turret floor, ammunition storage in the T-72 is open and generally in brackets. There are propellant cases and projectiles stowed behind both the gunner's and commander's seats, the rounds behind the commander's seats seen here at the top of the image and include two subcaliber projectiles and two propellant cases (black). There is a large under floor fuel tank between the rear of the turret floor and the firewall, and some propellant cases are stowed vertically in recesses in this fuel tank. Up front, there is another fuel tank to the right of the driver, and at the far left of the illustration you can see that additional rounds and propellant cases are stowed in a similar fashion recessed into the fuel tank, but now horizontally. A number of rounds are stowed on the hull wall at the rear of the T-72, and a few propellant cases are strapped to the turret floor at the feet of both gunner and commander. Again notice that in the carrousel, the propellant cases are placed in each cassette above the corresponding projectile. Although it is difficult to see in this illustration, the location of both types of MG ammo boxes is also shown, mostly on the commander's side of the turret.

Picture 13:
Our final drawing enlargement shows again the gunner's two primary sights. Recall that we are in an early T-72 with the biocular coincidence rangefinder. The laser rangefinder sight system that replaced the coincidence type in the T-72A and later vehicles has only one ocular, unlike what you see here. A typical gunner drill in a vehicle equipped with the laser rangefinder sight would go something like this: To bring the main gun into action the gunner first switches on the gyro drive of the TPD-K1 day sight (in a T-72A or T-72M1). After warm up, he then uncages the gyro for the field of view stabilizer and releases the elevating mechanism while switching on the stabilizer. The systems are now ready for action and the gunner can begin scanning the battlefield while using his sight and traversing the turret using his twin duplex control handles, or he can wait for the commander to designate a target and traverse the turret to it for him. Unlike most Western tanks, the gunner's powered traverse handles do not tilt to direct traverse, but they simply rotate in the horizontal plane.

Although not seen in this drawing, the gunner's hatch opens forward and has a circular opening in it for installing the snorkel for deep fording. In front of the hatch is a TNP-160 day periscope, while a TNPA-65 vision block is mounted in the hatch cover. In front and to the left of the hatch are the armored covers for the two sights mounted on the roof of the turret mentioned earlier.

Picture 14:
Here is a schematic drawing of the TPD-K1 laser rangefinder sight. In this case, the controls for the autoloader have not been attached. The controls along the top of the sight that would be closest to the turret ceiling include the emergency ammo selector switch (11) for times when electricity is not available. Ballistic data is stored on curved discs and when the autoloader is fully functional this switch has no effect. The indicator lights (10) are next to the emergency selector. Along the right side of the sight box is a correction value setting knob (16) and indicator lights for the laser rangefinder READY (20), meaning the system is in ready status. The other two lights are SETTING (22), which goes out after a measurement is taken and then shines again when the laser is again set to go-normally around six seconds interval. The final light indicates whether the system is in AUTO/HAND (23). Next to the lights is a box that houses the digital readout for the rangefinder (21) and close range target indicator light (24) and setting knob (25).

The three switches above the handgrips are for the sight stabilizer controls (2, 29, 30) with their indicator light panel (28) to the right. Under the ocular is the dioptic setting knob (6) and to the left is the brightness control (7) for the graticle. As you will see later, the additional small control panel for the autoloader will be attached below and to the left of the stabilizer controls.

Picture 15:
An old Soviet publicity photo shows a tanker in the gunner's seat working on the autoloader system in a T-72. This image provides a good idea of the scale of the interior of the turret, and the closeness of the surrounding components. The very wide angle of the camera lens distorts the edges of the picture and makes the interior appear roomier than it actually is. His TPD-K1 rangefinder sight is behind his left shoulder. The equipment he is handling appears to be part of the stub ejector system; his left hand is on the opening lever that actuates the ejection port cover. There are two motors that control the action of the autoloader at the back of the turret; one actuates the hoist bringing ammo up from the carrousel to the rear of the breech, and the second opens the stub ejection port. This stub ejection port electric motor is difficult to see in this photo, but it is behind the actuating lever the tanker is working on.

Picture 16:
Once the gunner has used his laser range finder (or stadiametric graticule) to determine the distance to his target, he then selects the desired type of ammunition via the knob near the stabilizer grips. He then presses his load button on his autoloader control panel, and the autoloader then prepares the gun for firing, the gunner being careful to keep his right arm away from the loading mechanism. If the gunner is engaging a moving target, the ballistic computer in the sight measures the signal produced as the gunner tracks the target by rotating the turret, and the sight graticule then will displace sideways to provide the necessary lead angle. The gunner then has to realign the graticule aiming point back onto the target, and then he can fire the weapon by pulling the trigger on the front of the left or right power control handle. The coax 7.62mm PKT MG is also aimed in the same way, but of course the ammunition selection knob at the top of the sight has to be set for coax MG.

This picture is the graticule view when looking through the TPD-K1 sight, but without the laser range circle illuminated. At the top of the sight picture is the target-range scale and the horizontal line with the triangles running across the center is the main aiming mark, with lead angle markers to either side. Below the lead markers is a vertical scale for the two ballistic graticules, one for HEAT rounds on the left, and the other for HE-FRAG rounds on the right. The scale off to the far right is a stadiametric rangefinder (using size of target to determine range) that assumes an average target height of around 2m and provides approximate ranges accordingly, from 40 at the left end of the scale to 5 at the far right, in increments of 5. Let's take a closer look at the coax mounted on the commander's side of the vehicle.

Picture 17:
The following description of the 7.62mm PKT tank machine gun comes from the US Army manual on Soviet equipment (FM 100-2-3). The 7.62-mm general-purpose machine gun, Pulemyot Kalashnikov (PK), is a gas-operated, belt-fed, sustained-fire weapon. The Soviets based its design on the Kalashnikov assault rifle. Notable differences from the assault rifle are the gas cylinder located below the barrel and the hollow-frame stock resembling that of the SVD sniper rifle. The PKM fires 7.62 x 54R rimmed cartridges using a metal non-disintegrating belt. The basic PK model is bipod-mounted and fed by a 100-round belt carried in a box fastened to the right side of the receiver. It weighs around nine kilograms and is 1161 millimeters long. Most of the weapon is constructed of stamped metal and forged steel. The PKS is a PK mounted on a lightweight (4.75-kg) tripod. It uses either a 200 or 250 round belt. The belt feeds from a box placed to the right of the weapon.

The PKT is the tank-mounted version of the PK. Late-model Soviet tanks, turreted APCs and ICVs, and amphibious scout cars mount the MG as a coaxial machine gun. It has a longer and heavier barrel than the PK and lacks the PK's stock, sights, bipod, and trigger mechanism. The PKT has a solenoid at the rear for electrical remote-controlled firing, although it also has an emergency manual trigger. The image is a Kalashnikov publicity photo.

Picture 18:
As we have seen, the gunner's IR night sight is to the left of the day sight, but firing at night is not as easy, nor accurate, as with Western tanks. In the M-60 and later M1 Abrams and Leopard 2 for example, the gunner simply switches over to the thermal image channel and continues firing with the same sight and controls. But in the T-72, the gunner has to switch over to the TPN1-49 IR night sight (in the T-72A/M1) and also has to use the large L-2 IR searchlight mounted on the right side of the main armament for active IR. This large IR searchlight has a limited range of 800m, and the enemy can easily spot the active IR. Also, the laser rangefinder and computer generated angle of sight cannot be used at night, which puts the T-72A at a real tactical disadvantage. This fact helps explain the dismal kill record of Iraqi T-72 gunners when engaged by coalition forces at night during Operation Desert Storm. Like this unfortunate T-72M1, they did not have an opportunity to engage targets at the distance required in modern warfare.

Okay, let's climb into one of the preserved T-72s we have lined up for you outside, and see how all this looks when sitting inside the real thing.








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